In recent years, the influence of global climate change is more significant, such as the extreme rainfall events have occurred frequently. In general, the L-moments are adopted and all data are usually given the equal weighting in conventional approach of rainfall frequency analysis. However, the consequence problem is that the return periods are always estimated higher for those extreme rainfall (or higher tail) events of recently occurring. Wang (1997) first introduced the idea of LH-moments, increasing the weighting of high tail parts of Generalized Extreme Value (GEV) distribution were developed for frequency analysis of extreme rainfall event. Moreover, Yu et al. (2012) derived the general form for various weighting factor m of LH-moments of GEV and also real applied to estimating the return period of extreme rainfall in Taiwan. The purpose of this study is to explore an approach of LH-moments for Pearson Type III distribution (PT3). First of all, the synthetic data of various parameter sets are generated to evaluate the rationality of return period estimate of LH-moments for data at high tail part of PT3. Eventually, it is hopeful that this study can be further adopted to play a referential role on application of hydrologic design.